This method of installation uses the chroot command to gain access to the broken system's files. Once the chroot command is issued, the LiveCD treats the broken system's / as its own. Commands run in a chroot environment will affect the broken systems filesystems and not those of the LiveCD.

1) Boot to the LiveCD Desktop (Ubuntu 9.10 or later). Please note that the Live CD must be the same as the system you are fixing - either 32-bit or 64-bit (if not then the chroot will fail).

2) Open a terminal (Applications > Accessories > Terminal).

3) Determine your normal system partition - (the switch is a lowercase "L")

sudo fdisk -l

If you aren't sure, run

df -Th

Look for the correct disk size and ext3 or ext4 format.

4) Mount your normal system partition:

Substitute the correct partition: sda1, sdb5, etc.

sudo mount /dev/sdXX /mnt

Example: sudo mount /dev/sda1 /mnt

5) Only if you have a separate boot partition:
sdYY is the /boot partition designation (for example sdb3)

Are you using a 64bit cd in a 64bit installed system? (or a 32bit cd in a 32bit installed system). Make sure you are not using a 64bit cd in a 32bit installed system neither a 32bit cd in a 64bit installed system.
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desguaMar 29 '12 at 20:52

Yes I am using 64 bit cd or 64 bit system. Does the version of linux also affect this?
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StarxMar 30 '12 at 4:27